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Despite the importance of and current demand for abaca (Musa textilis Nee) fiber, there has been limited study that capitalizes on RNA-seq to identify candidate genes associated with high fiber quality and bunchy top virus (AbBTV) resistance. Three varieties (Abuab, Inosa, and Tangongon), one wild banana variety (Musa balbisiana Colla) Pacol, and two developed backcrosses (Abuab × Pacol BC2 and BC3) were grown at the Institute of Plant Breeding (IPB), Laguna, Philippines. The pseudostems of 3-month-old suckers of each genotype were sampled for RNA-seq. Datasets were analyzed for differential expression (DE) implementing various model frameworks, including pairwise, genotypic and non-DE models. Results indicate that Abuab and BC3 induce the highest proportion (70%) of abaca-specific genes. Gene ontology (GO) enrichment analysis showed several genes associated with cellulose synthase activity, callose synthase, ß-glucosidase activity, glucan biosynthetic process, etc. KEGG pathway analysis showed several genes encoding for enzymes involved in the lignin biosynthetic pathway. Analysis using genotypic DE (GDE) between abaca bunchy top virus (AbBTV)-resistant and -susceptible groups revealed genes such as pathogenesis-related protein and NBS-LRR. As the genotypes were not infected with the pathogen, these genes are yet to be confirmed for their roles in disease resistance and are an interesting subject for further investigation.

The Musa textilis var. Abuab has high fiber quality (FQ) but has low resistance against abaca bunchy top virus (AbBTV); the Musa balbisiana var. Pacol, has low FQ but high resistance against AbBTV. Their backcrosses (BC2 and BC3) possess both desirable traits. Analysis using RNA-seq showed that the regulatory divergence of Abuab and Pacol is largely explained by cis differences with 27.4% and 22.3% if we are to assess it using BC2 and BC3, respectively. Cis differences between the two genotypes are significantly reduced from BC2 to BC3 due to changes in genomic constitution. Trans, on the other hand, is robust to changes in allelic composition. All these are attributed to the loss of heterozygosity in the BC3 relative to BC2. Further analysis showed that both backcrosses exhibited genome-wide preferential expression of Pacol- over Abuab-specific alleles, despite the wider genetic presence of the latter in the hybrids. The ratio of the two genotype-specific expressed transcripts and the ratio of their corresponding genetic make-up are significantly disproportionate, a phenomenon which we refer here as “genome–transcriptome incongruence”. We also observed preferential expression switching in which several genes prefer Abuab- (or Pacol-) specific allele in the BC2 but switched to Pacol- (or Abuab-) specific allele in the BC3 genome.

The indica ecotypes, IR64, an elite drought-susceptible variety adapted to irrigated ecosystem, and Apo (IR55423-01 or NSIC RC9), a moderate drought-tolerant upland genotype together with their hybrid (IR64 × Apo) were exposed to non- and water-stress conditions. By sequencing (RNA-seq) these genotypes, we were able to map genes diverging in cis and/or trans factors. Under non-stress condition, cis dominantly explains (11.2%) regulatory differences, followed by trans (8.9%). Further analysis showed that water-limiting condition largely affects trans and cis + trans factors. On the molecular level, cis and/or trans regulatory divergence explains their genotypic differences and differential drought response. Between the two parental genotypes, Apo appears to exhibit more photosynthetic efficiency even under water-limiting condition and is ascribed to trans. Statistical analyses showed that regulatory divergence is significantly influenced by environmental conditions. Likewise, the mode of parental expression inheritance which drives heterosis (HET) is significantly affected by environmental conditions indicating the malleability of heterosis to external factors. Further analysis revealed that the HET class, dominance, was significantly enriched under water-stress condition. We also identified allelic imbalance switching in which several genes prefer IR64- (or Apo-) specific allele under non-stress condition but switched to Apo- (or IR64-) specific allele when exposed to water-stress condition.

Epigenetics, which affects the phenotypes of various plants during development, is brought about by several environmental influences. In this chapter, we discuss DNA methylation in plants and cite some instances of phenotypic variations associated with such epigenetic changes, with special emphasis on the coconut. We describe how methylomic variation affects in vitro culture and endosperm development. We further cite how such methylomic changes can alter the phenotype of oil palm (Elaeis guineensis Jacq.) endosperm, a closely related species of coconut, which led to its decreased viability and loss of oil yield. These epigenetic changes are most likely caused by the alteration in the levels of DNA methylation in the affected somaclonal plants leading to phenotypic plasticity. Naturally occurring variants in the soft coconut endosperms such as the Makapuno and Lono are mass-cultivated through in vitro means, such as via tissue culture.

Mung bean is a well-known good source of protein. To increase its bioactivity, economic value, and nutritional content as a functional food and food additive, lactostatin (IIAEK), a cholesterol-lowering bioactive peptide, was engineered into mung bean 8S&alpha, globulin, a major storage protein. The results showed that the mutated 8S&alpha, globulin has a significant bile acid binding capacity (cholesterol-lowering activity) up to 47.25%. Moreover, superimposed mutant (Mut2) and wild-type (Wt) 3D protein structures showed a 93&ndash, 97% identity, indicating that the mutant proteins are stable. Ultra-performance liquid chromatography(UPLC)-based assay showed similar retention time for wild-type and mutant protein samples. Both IIAEK peptide standard and Mut2 digest had comparable baseline peaks corresponding to the same molecular size based on the liquid chromatography-mass spectrometry (LC-MS) data. A 573.36-Da mass spectrum was seen in Mut2, which indicates that Mut2 8S&alpha, globulin has been successfully mutated and digested to release the bioactive peptide, IIAEK. In vitro bile acid binding capacity showed that the 6-h Wt and 12-h engineered protein (Mut2) digests had the highest activity. Lastly, potential allergenicity was checked in the Allergen Database for Food Safety (ADFS) and the AllerBase database, and the IIAEK peptide matched the Bos d 5 epitopes. This study provides a strong foundation and basis for mung bean nutrition improvement, development of cholesterol-lowering food supplements, and protein engineering of other food proteins.

Organic sources of biodiesel such as microalgae are considered as potential renewable energy resources. These organisms are considered as sunlight-driven cellular factories that convert carbon dioxide to high amounts of lipids that can be used for biofuel production. This paper describes the possibility of using Desmodesmus sp. (I-AU1) for biodiesel production by evaluating its fatty acid profile distribution pattern and estimating the fuel-derived physical and chemical properties from fatty acid methyl esters (FAMEs) obtained from the trans-esterified microalgal oil. Growth rate, oil content, biomass, and lipid productivity of the algal strain have been investigated under nitrogen-starved (0.375 g L−1 NaNO3 in BG 11 medium) autotrophic condition for 22 days. Maximum average biomass yield of Desmodesmus sp. (I-AU1) is 0.745 g L−1 having 36.14% lipid content per dry weight of biomass, with a specific growth rate of 0.20 day−1. Fatty acid profiling of the biodiesel obtained from Desmodesmus sp. (I-AU1) contained total saturated fatty acid (SAFA) methyl esters of 31.02%, while the total monounsaturated fatty acid (MUFA) (C18:1) is 25.64%. Percentage composition of SAFA and MUFA for the microalga was 56.66%, which is high compared to that of most of related studies. Fuel properties were determined by empirical equations and were found to be within the limits of biodiesel standards ASTM D6751 (American) and EN 14214 (European). The quality properties of the biodiesel were low density (0.88 g cm−3), low kinematic viscosity (2.81 mm2 s−1), cetane number (43.47), oxidation stability (5.96 h), and cold filter plugging point (−7.41 °C). Hence, Desmodesmus sp. (I-AU1) has potential as a feedstock for the production of quality biodiesel.

Abstract cis and/or trans regulatory divergence within or between related taxa on a genome-wide scale has been largely unexamined in crops, more so, the effect of stress on cis/trans architecture. In this study, the indica genotypes IR64, an elite drought-susceptible lowland variety, and Apo (IR55423-01 or NSIC RC9), a moderate drought-tolerant upland genotype together with their hybrid (IR64 × Apo) were exposed to non- and water-stress conditions. Evidence of cis and/or trans regulatory differences was tested between these two indica rice genotypes. By sequencing (RNA-seq) the parents and their hybrid, we are able to map genes diverging in cis and/or trans factors between the two genotypes. Under non-stress conditions, cis dominantly explains (11.2%) regulatory differences, followed by trans (8.9%). Further analysis showed that water-limiting conditions largely affect trans and cis + trans factors. Between the two inbred lines, Apo appears to exhibit higher expression fold change of genes enriched in “response to stress” and “photosynthesis” under non- and water-stress conditions. On the molecular level, cis and/or trans regulatory divergence explains their genotypic differences and differential drought response. Parent–hybrid RNA-seq has the potential to identify genes diverging in cis and/or trans factors even between intra-sub-specifically related genotypes. By comparing cis/trans landscape under stressed and unstressed conditions, this approach has the ability to assess the impact of drought on gene expression. Computational analysis and association of several drought-yield QTL markers with cis-diverging genes provide converging evidences suggestive of a potential approach to identify trait-associated candidate genes using hybrids and their parents alone.Key Messagecis dominantly explains divergence of two indica rice genotypes, IR64 and Apo under normal conditions while trans and cis + trans regulatory factors are largely affected by drought

The seed oil of “batuan” [Garcinia binucao (Blco.) Choisy] fruit, an indigenous, lesser known, and with promising economic potential, was characterized to evaluate its quality and potential for product development. Using standard AOAC methods, thin layer chromatography and gas chromatography, the physicochemical properties, lipid and fatty acid profile were determined. Oil yield from “batuan” seeds was high. The extracted oil was yellowish white, soft solid at room temperature. Iodine value, acid value, and peroxide value of the seed oil were low while saponification value was high. Lipid presents in “batuan” seed oil is mostly triglycerides while diglycerides are in low amount. Unsaponifiable matter (

Leaf appearance and leaf elongation rates in rice play an essential role in determining the development of the plants' architecture which affects their adaptability to varying environments. This study aimed to characterize the rates of leaf appearance and elongation on all leaves of the main culms of rice plants for 11 contrasting varieties and to determine if the decrease in the leaf appearance rate was related to a simultaneous decrease in the rate of leaf elongation. Forty four 13-L pots were sown with one plant from one genotype and laid out in 4 randomized complete blocks. The experiment, conducted inside a greenhouse, was repeated twice. The increase in length of the leaves expanding on the main stems was monitored daily until flag leaf. Data were used to estimate the rates of leaf appearance and leaf elongation. Significant variability in the rate of leaf appearance, rate of leaf elongation, and leaf length was found across varieties. The kinetics of leaf appearance had linear phases intermediated by a curvilinear phase, without sharp changes in the phyllochron duration. Maximal leaf elongation rate (LER) of all genotypes (except for one) increased linearly with leaf rank until it reached its maximum value at leaf 8 to 10 (11 - 12 for Azucena) where it stabilized before decreasing linearly with leaf rank for the last leaves. Finally, both rates of leaf appearance and leaf elongation evolved with time more smoothly than expected so no sharp decrease in LER occurred at the time of the decrease in leaf appearance rate of the last leaves. However, the trilinear model fits the data well enough to remain useful in efficiently comparing the leaf appearance kinetics of contrasting varieties.

“Batuan” [Garcinia binucao (Blco.) Choisy], an indigenous, lesser known member of the Gutifferae family with export potential is underutilized and understudied. The present study was carried out to extract and characterize the protein in “batuan” [Garcinia binucao (Blco.) Choisy] seeds for nutritional quality assessment. Protein content of “batuan” seed meal was 8.9 ± 0.59% dry basis. Solubility fractionation of “batuan” seed meal showed globulin and glutelin as the major seed proteins. SDS-PAGE resolved the globulin and glutelin into three groups of polypeptides with molecular weights of about 20 – 54 kDa. Amino acid analysis revealed that seed protein contained all the essential amino acids with leucine as the most abundant while tryptophan, the least. “Batuan” seed proteins were mostly made up of acidic and hydrophobic amino acids with glutamic acid (2.67%) as the highest. Nutritional assessments including E/T (38.4%), amino acid score (1.6%), predicted PER (3.2-3.7) and estimated BV (98.3%) suggested that the seed proteins are of good quality. Hence, “batuan” seeds has a promising potential as an important sources of valuable proteins and amino acids for use as food supplement/enhancing ingredient.

The physicochemical properties and nutritional profile of the different parts and stages of maturity of “batuan” [ (Blco.) Choisy] fruits in the Visayas State University (VSU) were determined using standard analytical methods to validate their use as a safe food ingredient. Sensory evaluation on the acceptability of the dry, powdered “batuan” fruits as souring agent in fish stew dish was also conducted. Proximate composition, physicochemical properties and nutrient composition between parts and fruit maturity varied to some level. The pulp which constituted the biggest part of the fruit and the immature ones contained high moisture and acidity that decreased as the fruit matured. Ash, protein, sugar, starch, total carbohydrates, total soluble solids, and sodium content were low in “batuan” fruits. The seeds contained high crude fat, crude protein, and tannin. “Batuan” fruits were also found high in vitamin C, potassium, phosphorus, calcium, magnesium, iron, and trace levels of zinc, copper and manganese. Crude fiber and vitamin A were concentrated in the peel, pulp and ripe fruit. Based on the 9-point Hedonic scale for sensory evaluation, the fresh and the dry, powdered “batuan” fruits were comparable to one another in terms of color, mouth feel, taste and general acceptability as souring agent for fish stew. Results showed that “batuan” fruits have good physicochemical properties and nutrient contents which are comparable or even higher than some conventional fruits used as souring agents. The powdered “batuan” fruit is a potential ready-touse souring agent for domestic consumption, food industry, and other applications.

Papaya is a climacteric fruit and like other climacteric fruits in the tropics, one of the main problems is the significant post-harvest loss due to uncontrolled ripening. One molecular strategy to control ripening after the climacteric rise in ethylene is to down-regulate ethylene biosynthesis through antisense expression of the ripening-related ACC synthase gene. Total RNA was isolated from 100% ripe papaya fruit and reverse transcriptase polymerase chain reaction (RT-PCR) was used to amplify ripening-related ACC synthase cDNAs. Two pairs of degenerate primers (oligonucleotides) derived from conserved regions of ACC synthase from several plant sources were used for RT-PCR. Two different members of the ACC synthase multigene family were isolated and characterized from ripe tissues of papaya whose expression patterns differ greatly from each other. The two ACC synthase cDNAs, ACS1 and ACS2 differ from each other in terms of restriction digest patterns, DNA and amino acid sequence analysis and expression during ripening. ACS2 expression pattern in papaya cv Solo Kapoho exhibits a striking similarity to that of leacs2 in tomato whose transcript levels are high during ripening. ACS2 is a good candidate gene of ACC synthase for antisense strategies to regulate or control fruit ripening. ACS2 was inserted in an antisense orientation in two types of vector constructs for papaya transformation via particle bombardment.

Papaya (cv. Solo) somatic embryos were produced, squashed and used for transient stable transformation. Conditions for transforming somatic embryos were optimized using transient expression of GUS. A total of 11,900 immature zygotic embryos were isolated and 7,730 (65%) produced somatic embryos. All the somatic embryos were squashed, placed in an osmotic medium and bombarded with the antisense ACC synthase construct placed in a co-transformation vector. A total of 160 bombardments were made. The bombarded tissues were subjected to a selection medium containing half-strength MS with 150 mg L-1, then with 300 mg L-1 kanamycin. Embryos surviving kanamycin-selection were regenerated on a full strength De Fossard medium supplemented with 0.25 muM each of BAP and NAA and 10.0 muM GA(3).

The levels of antinutritional and toxic factors were determined in several Philippine indigenous legumes, namely, hyacinth bean (Dolichos lablab L.) lima bean (Phaseolus lunatus L.), sabawel or velvet bean (Mucuna curanii), sam-samping (Clitoria ternatea), rice bean (Vigna umbellata), jackbean (Canavalia ensiformis), and swordbean (Canavalia gladiata). Low levels of condensed tannins (0–2.48 mg catechin /g) and protein-precipitable polyphenols (0.16–0.77 mg tannic acid/gram) were observed in raw mature seeds of the six legumes analyzed in this preliminary study. Seeds of hyacinth bean, jackbean, and lima bean had relatively high levels of phytate phosphorus ranging from 6.6 to 11.6 mg of phytate P/g of sample. Lower values (

Previous attempts to express the human immunodeficiency virus 1 (HIV-1) Tat (trans-activator of transcription) protein in plants resulted in a number of physiological abnormalities, such as stunted growth and absence of seed formation, that could not be explained. In the study reported here, we expressed Tat in tomato and observed phenotypic abnormalities, including stunted growth, absence of root formation, chlorosis, and plant death, as a result of reduced cytokinin levels. These reduced levels were ascribed to a differentially expressed CKO35 in Tat-bombarded tomato. Of the two CKO isoforms that are naturally expressed in tomato, CKO43 and CKO37, only the expression of CKO37 was affected by Tat. Our analysis of the Tat confirmed that the Arg-rich and RGD motifs of Tat have functional relevance in tomato and that independent mutations at these motifs caused inhibition of the differentially expressed CKO isoform and the extracellular secretion of the Tat protein, respectively, in our Tat-bombarded tomato samples.

HIV-1 Tat plays a major role in viral replication and is essential for AIDS development making it an ideal vaccine target providing that both humoral and cellular immune responses are induced. Plant-based antigen production, due to its cheaper cost, appears ideal for vaccine production. In this study, we created a plant-optimized tat and mutant (Cys30Ala/Lys41Ala) tat (mtat) gene and ligated each into a pBI121 expression vector with a stop codon and a gusA gene positioned immediately downstream. The vector construct was bombarded into tomato leaf calli and allowed to develop. We thus generated recombinant tomato plants preferentially expressing a Tat-GUS fusion protein over a Tat-only protein. In addition, plants bombarded with either tat or mtat genes showed no phenotypic difference and produced 2-4 microg Tat-GUS fusion protein per milligram soluble plant protein. Furthermore, tomato extracts intradermally inoculated into mice were found to induce a humoral and, most importantly, cellular immunity.

This study demonstrates variability in amino acid composition among accessions of several Philippine indigenous legumes. Moreover, two accessions of D. lablab were identified to have high level of methionine (greater than 2%). Methionine was identified as the first limiting amino acid with leucine, and threonine as the second limiting amino acids for most legumes studies. The IVPDs of the legumes under study ranged from greater than 70 to 79%. Raw mature seeds had relatively low RNVs of 11 to 68% which increased to 68 to 94% and 51 to 89% after boiling and roasting, respectively.

Papaya with resistance to papaya ringspot virus (PRSV) is the first genetically modified tree and fruit crop and also the first transgenic crop developed by a public institution that has been commercialized. This chapter reviews the different transformation systems used for papaya and recent advances in the use of transgenic technology to introduce important quality and horticultural traits in papaya. These include the development of the following traits in papaya: resistance to PRSV, mites and Phytophthora, delayed ripening trait or long shelf life by inhibiting ethylene production or reducing loss of firmness, and tolerance or resistance to herbicide and aluminum toxicity. The use of papaya to produce vaccine against tuberculosis and cysticercosis, an infectious animal disease, has also been explored. Because of the economic importance of papaya, there are several collaborative and independent efforts to develop PRSV transgenic papaya technology in 14 countries. This chapter further reviews the strategies and constraints in the adoption of the technology and biosafety to the environment and food safety. Constraints to adoption include public perception, strict and expensive regulatory procedures and intellectual property issues.

Papaya with resistance to papaya ringspot virus (PRSV) is the first genetically modified tree and fruit crop and also the first transgenic crop developed by a public institution that has been commercialized. This chapter reviews the different transformation systems used for papaya and recent advances in the use of transgenic technology to introduce important quality and horticultural traits in papaya. These include the development of the following traits in papaya: resistance to PRSV, mites and Phytophthora, delayed ripening trait or long shelf life by inhibiting ethylene production or reducing loss of firmness, and tolerance or resistance to herbicide and aluminum toxicity. The use of papaya to produce vaccine against tuberculosis and cysticercosis, an infectious animal disease, has also been explored. Because of the economic importance of papaya, there are several collaborative and independent efforts to develop PRSV transgenic papaya technology in 14 countries. This chapter further reviews the strategies and constraints in the adoption of the technology and biosafety to the environment and food safety. Constraints to adoption include public perception, strict and expensive regulatory procedures and intellectual property issues.

Five ripening-related ACC synthase cDNA isoforms were cloned from 80% ripe papaya cv. 'Sinta' by reverse transcription-PCR using gene-specific primers. Clone 2 had the longest transcript and contained all common exons and three alternative exons. Clones 3 and 4 contained common exons and one alternative exon each, while clone 1, the most common transcript, contained only the common exons. Clone 5 could be due to cloning artifacts and might not be a unique cDNA fragment. Thus, there are only four isoforms of ACC synthase mRNA. Southern blot analysis indicates that all five clones came from only one gene existing as a single copy in the 'Sinta' papaya genome. Multiple sequence alignment indicates that the four isoforms arise from a single gene, possibly through alternative splicing mechanisms. All the putative alternative exons were present at the 5'-end of the gene comprising the N-terminal region of the protein. 'Sinta' ACC synthase cDNAs were of the capacs 1 type and are most closely related to a 1.4 kb capacs 1-type DNA (AJ277160) from Eksotika papaya. No capacs 2-type cDNAs were cloned from 'Sinta' by RT-PCR. This is the first report of possible alternative splicing mechanism in ripening-related ACC synthase genes in hybrid papaya, possibly to modulate or fine-tune gene expression relevant to fruit ripening.

The papaya (Carica papaya L.) is usually being harvested when they are about 25% ripe or when a tinge of yellow color appears on the skin. It takes only one to two weeks before the fruit ripens completely from the time of harvest. Losses due to postharvest diseases in some species reach up to about 60% of annual production. The two most important qualities required for efficient marketing of fruits are the taste and the overall appearance. The flexibility in marketing is determined mainly by the rate of fruit ripening. An extended ripening phase would prolong its shelf-life, thus allowing the fruit to be shipped to distant markets without spoilage, thereby increasing the potential target markets, and enabling the fruit to reach the market in better condition. The papaya is a climacteric fruit and ripening is in part, being controlled by the simple hydrocarbon ethylene. The rate-limiting enzyme of the ethylene biosynthetic pathway is ACC synthase. This enzyme has been the target in engineering the ethylene biosynthesis pathway using the antisense technology. This technology for instance has been used to reduce translation of either ACC synthase or ACC oxidase by antisense RNA that blocks ethylene production in tomato, thereby delaying fruit ripening (Oeller et al., 1991; Hamilton et al., 1991). Two ACC synthase genes expressed during fruit ripening have been cloned from papaya (Mason and Botella, 1997). These genes could be used for transforming papaya plants that could constitutively express an antisense copy of the ACC synthase gene. In this study, we aimed to apply antisense technology and the existing transformation protocol to produce transgenic Solo papayas.

One prerequisite to reliable molecular biology work is that the genomic DNA of a sample be of good quality. Coconut is quite difficult to work on because of the high lipid and polysaccharide content of its endosperm and the high polyphenol content of its leaves. This study aimed to determine which protocol to use and which part of the coconut tree is most appropriate to extract good-quality genomic DNA. Genomic DNA from the solid endosperm was found to be of poor quality because of high levels of lipid and galactomannan contaminants. By using a modified protocol by Cheung et al. (1993) as modified by Rogers et al. (1996) and by Dellaporta et al. (1983) as modified by Datta et al. (1997), genomic DNA extracted from the young leaves of the first emergent frond provided enzyme-digestible, good-quality DNA. The modification involved the use of a higher salt concentration (2 M instead of 0.5 M) in the extraction buffer and the use of polyvinylpolypyrrolidone. Moreover, this modified protocol did not involve the use of organic solvents.

Simple wet heat treatments like simple boiling (atmospheric pressure, 100 °C) and pressurized boiling (higher than 100 °C) reduced the polyphenol content of mature dark red seeds of cowpea (Vigna unguiculata (L.) Walp.) cultivar UPL Cp 3 by 61 to 80% and improved in vitro protein digestibility (IVPD) by 6 to 26%. Pressurized steaming (higher than 100 °C) removed 48 to 83% of the polyphenols but increased IVPD by only 1.1 to 4.2%. Dry heat as exemplified by roasting and microwave treatment inactivated 58 to 71% of the tannins but increased IVPD by only 1%. All the heat treatments were effective in removing/inactivating polyphenols though different responses were observed with the resulting in vitro protein digestibilities.

Mise en evidence, chez huit varietes differant par la couleur de leur tegument, d'une correlation entre teneur en tanins condenses et couleur des teguments. La cuisson ameliore la digestibilite. L'ingestion simultanee du milieu de cuisson modifie la digestibilite des graines cuites. On observe une correlation negative significative entre teneur en tanins condenses et digestibilite des proteines ou valeur nutritive relative

Mature dark red seeds of cowpea (Vigna unguiculata (L.) Walp.) UPL Cp 3, were subjected to several soaking treatments to remove their polyphenols. Soaking in water at room temperature for 8 and 24 h resulted in 17% and 21% loss of assayable polyphenols, respectively. Dilute solutions of alkali (Na2CO3, NaHCO3, NH4OH and KOH) and acid (CH3 COOH, HCl and H2 SO4) were more effective in removing polyphenols up to 88% than higher concentrations of alkali and acid solutions.

Turmeric (Curcuma longa L.) is currently considered a potential source of new drugs for a variety of diseases due to the presence of curcuminoids, the most important being curcumin. The existence of genetic diversity in turmeric is documented in other countries but not in the Philippines, where turmeric is an introduced species. This study aims to determine the possible existence of genotypic diversity among turmeric accessions in Mindanao, Philippines using random amplified polymorphic DNA (RAPD) markers. Ten random primers were used for RAPD analysis from which a total of 209 amplification products were generated. Almost all the bands generated were polymorphic indicating genetic diversity among the accessions. Six primers (OPD08, OPB07, OPA11, OPA12, OPC05 and OPN16) had polymorphic information content values of almost 0.5, thus, were able to discriminate between the turmeric genotypes. Effective multiplex ratio and marker index were also relatively high for the same six markers except for OPA12.